Method for repairing loose molded-in bushings

ABSTRACT

The present invention relates to a method for bonding a component, such as a bushing, into a part, such as a panel. The method broadly comprises attaching a vacuum chamber to a surface of the part, seating the component into a slot in the part, and applying an adhesive material about a circumference of the component while drawing a vacuum in the vacuum chamber to allow the adhesive material to flow between the part and the component.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a method for re-bonding acomponent, such as a bushing, which is mechanically locked into a part,such as a panel.

[0002] Components, such as bushings, molded into a part, such as acomposite panel, come loose as a result of wear and vibration duringservice and need to be re-bonded into position. Previous repairtechniques for performing such re-bonding involve either a staking ofthe component or drilling injection holes. One of the great difficultieswith these previous repair techniques is trying to get a proper flow ofthe adhesive material used to re-bond the component.

[0003] Thus, there remains a need for a repair technique whicheffectively re-bonds a loosened component into place.

SUMMARY OF THE INVENTION

[0004] Accordingly, it is an object of the present invention to providea method for re-bonding a component into a part. It is a further objectof the present invention to provide a method as above which obtains aproper flow of the adhesive material used to bond the component.

[0005] The foregoing objects are attained by the method of the presentinvention.

[0006] In accordance with the present invention, a method for re-bondinga component into a part is provided. The method broadly comprisesattaching a vacuum chamber to a surface of the part and applying anadhesive material about a circumference of the component while drawing avacuum in the vacuum chamber to allow the adhesive material to flowbetween the part and the component.

[0007] A system for performing the method of the present invention isalso disclosed.

[0008] Other details of the method of the present invention, as well asother objects and advantages attendant thereto, are set forth in thefollowing detailed description and the accompanying drawing wherein likereference numerals depict like elements.

BRIEF DESCRIPTION OF THE DRAWING

[0009] The FIGURE illustrates a system for bonding a component into apart.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

[0010] Referring now to the FIGURE, a system for re-bonding a component10, such as a bushing, which is mechanically locked into in a slot in apart 12, such as a panel, is illustrated. The system includes a vacuumchamber 14 secured to a surface 16 of the part 12, a means 18 fordepositing an adhesive all around the circumference of the component 10to be rebonded, and a manually operable tool 20 whose function will bedescribed hereinafter.

[0011] The vacuum chamber 14 may be locally manufactured from apolyvinylchloride pipe with an end cap or from any other suitable vesselknown in the art. The vacuum chamber may be secured to the surface 16 byany suitable means known in the art, such as by a sealant tape 22. Thevacuum chamber 14 may be connected to a vacuum source (not shown) via aconduit 24.

[0012] The manually operable tool 20 is used for two purposes. One toseal the inside of the bushing against leakage and Two to rock thebushing to break the seal between the bushing flange 36 and the panel12. As can be seen from the Figure, the tool 20 has an end portion 26which conforms to the shape of an opening 28 in the component 10. Forexample, the end portion 26 may have a conical portion 30 for engagingconical surfaces 32 in the opening 28 and a cylindrical tip portion 33for engaging a cylindrical portion 34 in the opening 28. As shown in theFigure, the tool 20 may be rocked from side to side to break any sealbetween the part 12 and a flange 36 which surrounds the component 10.This allows an adhesive material to better flow between the component 10and the part 12. The tool 20 also serves to plug the opening 28 while avacuum is being applied to the chamber 14.

[0013] The adhesive depositing means 18 may comprise any suitable meansknown in the art for applying an adhesive material between the component10 and the part 12. Preferably, the adhesive depositing means 18comprises a syringe.

[0014] The bonding method of the present invention may be performed byfirst cleaning the surface area around the component 10. Any suitabletechnique known in the art may be used to perform the cleaning step.Following cleaning, the component 10 and the part 12 are allowed to airdry. While the component 10 and the part 12 are drying, an adhesivesystem for securing the component 10 to the part 12 may be prepared. Theadhesive system may be any suitable adhesive material known in the artsuch as a 2 part liquid epoxy resin. If desired, the mixed adhesive maybe diluted with a suitable solvent to reduce viscosity. As previouslymentioned, the vacuum chamber 14 may be locally manufactured andattached to the back side of the part 12 using a sealant material suchas sealant tape 22. Once the vacuum chamber has been manufactured, thetool 20 may be used to plug the opening 28 in the component 10.

[0015] Thereafter, a vacuum may be drawn, typically 25 inches Hgminimum. While the vacuum is drawn, the mixed adhesive material isinjected into the gap 40 around the component 10. The adhesive materialis injected until it starts to appear out of the back side of the part12. Then, the vacuum source and the plug tool 20 are removed and theadhesive material is allowed to cure per the adhesive manufacturer'srecommended cure time and temperature. One of the advantages to themethod of the present invention is that the adhesive material may beapplied more completely around the component 10 to be bonded into thepart 12 as a result of the vacuum application. Further, the method ofthe present invention is easy to perform and does not require expensiveequipment.

[0016] The method of the present invention has particular utility inre-bonding of bushings that are mechanically locked in place at the timeof original manufacture and become loose during usage. Typical usage ofthis invention would include repairing front and rear liner panels ofturbine engines, where the mounting bushings have become loose due tocyclical temperature variations and vibration.

[0017] It is apparent that there has been provided in accordance withthe present invention a method for repairing loose molded-in bushingswhich fully satisfies the objects, means and advantages set forthhereinbefore. While the present invention has been described in thecontext of specific embodiments thereof, other alternatives,modifications, and variations will become apparent to those skilled inthe art having read the foregoing description. Accordingly, it isintended to embrace those alternatives, modifications, and variationswhich fall within the broad scope of the appended claims.

What is claimed is:
 1. A method for re-bonding a component into a partcomprising the steps of: attaching a vacuum chamber to a surface of saidpart; seating said component in a slot in said part; and applying anadhesive material about a circumference of said component while drawinga vacuum in said vacuum chamber to allow said adhesive material to flowbetween the part and the component.
 2. A method according to claim 1,further comprising cleaning a surface area around said component andallowing said surface area to dry.
 3. A method according to claim 1,wherein said adhesive material applying step comprises applying an epoxycontaining adhesive material.
 4. A method according to claim 3, furthercomprising diluting said epoxy containing material with a solvent priorto said applying step.
 5. A method according to claim 1, furthercomprising locally fabricating said vacuum chamber from a pipe having anend cap and said attaching step comprising affixing said locallyfabricated vacuum chamber to said part surface using a sealant material.6. A method according to claim 1, further comprising providing acomponent having a hole and plugging said hole in said component with aplug tool while said vacuum is applied.
 7. A method according to claim6, further comprising discontinuing said vacuum, removing said plugtool, and curing said adhesive material.
 8. A method according to claim1, wherein said part comprises a panel and said seating step comprisesseating a bushing into said panel.
 9. A method according to claim 1,wherein said vacuum drawing step comprises drawing a 25 inch minimumvacuum.
 10. A method according to claim 1, wherein said adhesivematerial applying step comprises applying said adhesive material using asyringe into a gap around said component and continuing to apply saidadhesive material until adhesive material starts to appear out a backside of the component.
 11. A method according to claim 10, furthercomprising placing a plug tool into a hole in said part and rocking saidpart back and forth with said plug tool to break a seal between the partand the component to allow said adhesive material to flow.
 12. A systemfor bonding a component into a part comprising: means for applying anadhesive material to a gap surrounding said component; means forengaging an opening in said component and sealing said opening; andmeans for applying a vacuum to a side of said part while said adhesivematerial is being applied.
 13. A system according to claim 12, whereinsaid adhesive material applying means comprises a syringe containing anadhesive material.
 14. A system according to claim 12, wherein saidopening engaging means comprises a manually operable tool.
 15. A systemaccording to claim 14, wherein said tool has a cylindrical tip portionfor engaging and plugging a cylindrical portion of said opening.
 16. Asystem according to claim 15, wherein said tool further has a conicallyshaped portion for engaging and plugging a conically shaped portion ofsaid opening.
 17. A system according to claim 12, wherein said vacuumapplying means comprises a vacuum chamber attached to said side of saidpart.
 18. A system according to claim 17, wherein said vacuum chamber islocally manufactured from a polyvinylchloride pipe having an end cap.19. A system according to claim 17, further comprising a sealant tapefor securing said vacuum chamber to said part side.